Isotopically enriched mercury can be produced by a number of methods. One method involves photosensitized chemical reactions utilizing elemental mercury and various compounds. The compounds HCl and O.sub.2 react with mercury atoms when the mercury atoms are excited by resonance radiation, in particular, 2537A radiation produced in a Hg (.sup.3 P.sub.1 -.sup.1 S.sub.0) transition generating isotopically selective reactions. Thus, the Hg compound formed contains Hg enriched in a particular isotope, and the Hg must be separated from the compound into its free state in order to recover the isotopically enriched metal.
Although it has been possible to separate mercury from mercury compounds by a number of techniques, previously employed techniques suffer from significant disadvantages. For example, it has been possible to separate Hg from Hg.sub.2 Cl.sub.2 via electrolytic methods using a mixture of methanol and HCl as an electrolyte solution. However, this method produced low yields and the electrolyte solution had a tendency to become contaminated with impurities and to become blackened and corroded.
Hg can also be separated from HgO via thermal decomposition. However, this requires high temperature baking [T&gt;500.degree. C.] and it can easily result in the introduction of trace impurities into mercury. Additionally, vacuum baking at high temperatures requires hardware and techniques that are very complex.
Also, in the past the yield has been reduced and the danger of exposure to workers has been greatly increased due to the fact that photochemically produced mercury compounds had to be removed manually from the reaction container and then placed in a second container where the mercury was then separated from the mercury compounds.